I. Field of the Invention
This invention relates to vent dampers for controlling the flow of heated or cooled air through a vent, and, in particular, to an operating mechanism for opening and closing damper louvers.
II. Description of the Prior Art
Vent dampers are widely used to control the flow from heating and cooling systems into a specific room. Typical dampers include one or more louvers which can be moved between a closed position blocking flow through the damper and an open position. Rotatable louvers may be positioned to deflect air flow in a specific direction from the damper.
The control mechanism for moving the damper louvers have taken on a variety of configurations. The most common is a pivotable lever which simultaneously pivot the louvers. Such levers maintain a low profile yet facilitate simple operation of the damper. Alternatives include a rotatable gear which cooperates with toothed gears on the dampers. Rotation of the main gear transmits rotational motion to the dampers for control of air flow.
The present invention overcomes the disadvantages of the prior known vent dampers by providing a rack and pinion mechanism for translating linear motion of a lever to rotation of the dampers.
The vent damper embodying the present invention generally comprises a rectangular housing configured to fit within an outlet opening of the vent. This opening may be formed within the floor, wall or ceiling of a room to direct air flow from the heating and cooling system. Disposed within the housing are a plurality of damper vanes or louvers for selectively blocking air flow through the housing. The louvers are rotatably mounted to the housing for rotation between a closed position substantially perpendicular to the flow passageway of the housing and a full open position substantially parallel to the air flow. The louvers include end hubs which are rotatably received in apertures formed in the housing wall to support the louvers within the housing.
Each of the louvers include a pinion gear for independent rotation control of the individual louvers. In a preferred embodiment, a partial pinion gear is molded as part of the louver in association with one of the end hubs. As a result, rotation of the pinion will rotate the louver about the axis of the hub.
Mounted to the housing is a slidable lever which protrudes above the face of the damper for manipulation by the user. The lever is slidably received within a channel formed in the housing wall and includes a linear rack of teeth adapted to cooperate with the teeth of the pinion gears. The rack teeth are disposed downwardly for engagement with the pinion teeth of the louvers. As a result, linear movement of the lever along the housing wall will transmit motion to the pinions to rotate the louvers between the open and closed positions.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.